Brooklyn boy turned ice cream mogul Ben Cohen is returning to his home turf Tuesday with a mission: to stamp money out of politics.

Cohen, the "Ben" of Ben and Jerry's, is traveling the country with his "Amendomatic" to galvanize support for state laws to counter the Supreme Court's Citizens United decision that made corporate political donations protected as free speech.

"Money in politics is really the root of all the problems that we've got in this country," said Cohen. "Essentially, corporations and the wealthiest 0.01 percent are paying politicians hundreds of thousands of dollars to pass legislation that benefits them at the expense of everyone else."

Cohen will be in Union Square from noon to 2 p.m. Tuesday to mark dollar bills with a stamp declaring them "not to be used for bribing politicians." Cohen says he'll even be passing out a few of the dollar bills.

According to Cohen, 120 congressmembers are already on board with a constitutional amendment to counteractCitizens United.Cohen said he would be happy with either of two options: "an amendment saying corporations are not people and money is not free speech," or an amendment legislating that all elections be publicly funded.

A public financing amendment just failed in the New York State Senate last week because New York Democrats could not unify behind it. One of the Democrats who did not support the amendment was Senator Malcolm Smith, who was arrested in April for his part in an alleged plot to bribe his way into the Republican mayoral primary.